1 /*
2  * Copyright (C) 2015 Red Hat, Inc.
3  * All Rights Reserved.
4  *
5  * Permission is hereby granted, free of charge, to any person obtaining
6  * a copy of this software and associated documentation files (the
7  * "Software"), to deal in the Software without restriction, including
8  * without limitation the rights to use, copy, modify, merge, publish,
9  * distribute, sublicense, and/or sell copies of the Software, and to
10  * permit persons to whom the Software is furnished to do so, subject to
11  * the following conditions:
12  *
13  * The above copyright notice and this permission notice (including the
14  * next paragraph) shall be included in all copies or substantial
15  * portions of the Software.
16  *
17  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
18  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
19  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
20  * IN NO EVENT SHALL THE COPYRIGHT OWNER(S) AND/OR ITS SUPPLIERS BE
21  * LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
22  * OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
23  * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
24  */
25 
26 #include <linux/dma-mapping.h>
27 #include <linux/moduleparam.h>
28 
29 #include "virtgpu_drv.h"
30 
31 static int virtio_gpu_virglrenderer_workaround = 1;
32 module_param_named(virglhack, virtio_gpu_virglrenderer_workaround, int, 0400);
33 
34 int virtio_gpu_resource_id_get(struct virtio_gpu_device *vgdev, uint32_t *resid)
35 {
36 	if (virtio_gpu_virglrenderer_workaround) {
37 		/*
38 		 * Hack to avoid re-using resource IDs.
39 		 *
40 		 * virglrenderer versions up to (and including) 0.7.0
41 		 * can't deal with that.  virglrenderer commit
42 		 * "f91a9dd35715 Fix unlinking resources from hash
43 		 * table." (Feb 2019) fixes the bug.
44 		 */
45 		static atomic_t seqno = ATOMIC_INIT(0);
46 		int handle = atomic_inc_return(&seqno);
47 		*resid = handle + 1;
48 	} else {
49 		int handle = ida_alloc(&vgdev->resource_ida, GFP_KERNEL);
50 		if (handle < 0)
51 			return handle;
52 		*resid = handle + 1;
53 	}
54 	return 0;
55 }
56 
57 static void virtio_gpu_resource_id_put(struct virtio_gpu_device *vgdev, uint32_t id)
58 {
59 	if (!virtio_gpu_virglrenderer_workaround) {
60 		ida_free(&vgdev->resource_ida, id - 1);
61 	}
62 }
63 
64 void virtio_gpu_cleanup_object(struct virtio_gpu_object *bo)
65 {
66 	struct virtio_gpu_device *vgdev = bo->base.base.dev->dev_private;
67 
68 	virtio_gpu_resource_id_put(vgdev, bo->hw_res_handle);
69 	if (virtio_gpu_is_shmem(bo)) {
70 		struct virtio_gpu_object_shmem *shmem = to_virtio_gpu_shmem(bo);
71 
72 		if (shmem->pages) {
73 			if (shmem->mapped) {
74 				dma_unmap_sg(vgdev->vdev->dev.parent,
75 					     shmem->pages->sgl, shmem->mapped,
76 					     DMA_TO_DEVICE);
77 				shmem->mapped = 0;
78 			}
79 
80 			sg_free_table(shmem->pages);
81 			kfree(shmem->pages);
82 			shmem->pages = NULL;
83 			drm_gem_shmem_unpin(&bo->base.base);
84 		}
85 
86 		drm_gem_shmem_free_object(&bo->base.base);
87 	} else if (virtio_gpu_is_vram(bo)) {
88 		struct virtio_gpu_object_vram *vram = to_virtio_gpu_vram(bo);
89 
90 		spin_lock(&vgdev->host_visible_lock);
91 		if (drm_mm_node_allocated(&vram->vram_node))
92 			drm_mm_remove_node(&vram->vram_node);
93 
94 		spin_unlock(&vgdev->host_visible_lock);
95 
96 		drm_gem_free_mmap_offset(&vram->base.base.base);
97 		drm_gem_object_release(&vram->base.base.base);
98 		kfree(vram);
99 	}
100 }
101 
102 static void virtio_gpu_free_object(struct drm_gem_object *obj)
103 {
104 	struct virtio_gpu_object *bo = gem_to_virtio_gpu_obj(obj);
105 	struct virtio_gpu_device *vgdev = bo->base.base.dev->dev_private;
106 
107 	if (bo->created) {
108 		virtio_gpu_cmd_unref_resource(vgdev, bo);
109 		virtio_gpu_notify(vgdev);
110 		/* completion handler calls virtio_gpu_cleanup_object() */
111 		return;
112 	}
113 	virtio_gpu_cleanup_object(bo);
114 }
115 
116 static const struct drm_gem_object_funcs virtio_gpu_shmem_funcs = {
117 	.free = virtio_gpu_free_object,
118 	.open = virtio_gpu_gem_object_open,
119 	.close = virtio_gpu_gem_object_close,
120 
121 	.print_info = drm_gem_shmem_print_info,
122 	.export = virtgpu_gem_prime_export,
123 	.pin = drm_gem_shmem_pin,
124 	.unpin = drm_gem_shmem_unpin,
125 	.get_sg_table = drm_gem_shmem_get_sg_table,
126 	.vmap = drm_gem_shmem_vmap,
127 	.vunmap = drm_gem_shmem_vunmap,
128 	.mmap = drm_gem_shmem_mmap,
129 };
130 
131 bool virtio_gpu_is_shmem(struct virtio_gpu_object *bo)
132 {
133 	return bo->base.base.funcs == &virtio_gpu_shmem_funcs;
134 }
135 
136 struct drm_gem_object *virtio_gpu_create_object(struct drm_device *dev,
137 						size_t size)
138 {
139 	struct virtio_gpu_object_shmem *shmem;
140 	struct drm_gem_shmem_object *dshmem;
141 
142 	shmem = kzalloc(sizeof(*shmem), GFP_KERNEL);
143 	if (!shmem)
144 		return NULL;
145 
146 	dshmem = &shmem->base.base;
147 	dshmem->base.funcs = &virtio_gpu_shmem_funcs;
148 	dshmem->map_cached = true;
149 	return &dshmem->base;
150 }
151 
152 static int virtio_gpu_object_shmem_init(struct virtio_gpu_device *vgdev,
153 					struct virtio_gpu_object *bo,
154 					struct virtio_gpu_mem_entry **ents,
155 					unsigned int *nents)
156 {
157 	bool use_dma_api = !virtio_has_dma_quirk(vgdev->vdev);
158 	struct virtio_gpu_object_shmem *shmem = to_virtio_gpu_shmem(bo);
159 	struct scatterlist *sg;
160 	int si, ret;
161 
162 	ret = drm_gem_shmem_pin(&bo->base.base);
163 	if (ret < 0)
164 		return -EINVAL;
165 
166 	/*
167 	 * virtio_gpu uses drm_gem_shmem_get_sg_table instead of
168 	 * drm_gem_shmem_get_pages_sgt because virtio has it's own set of
169 	 * dma-ops. This is discouraged for other drivers, but should be fine
170 	 * since virtio_gpu doesn't support dma-buf import from other devices.
171 	 */
172 	shmem->pages = drm_gem_shmem_get_sg_table(&bo->base.base);
173 	if (!shmem->pages) {
174 		drm_gem_shmem_unpin(&bo->base.base);
175 		return -EINVAL;
176 	}
177 
178 	if (use_dma_api) {
179 		shmem->mapped = dma_map_sg(vgdev->vdev->dev.parent,
180 					   shmem->pages->sgl,
181 					   shmem->pages->nents,
182 					   DMA_TO_DEVICE);
183 		*nents = shmem->mapped;
184 	} else {
185 		*nents = shmem->pages->nents;
186 	}
187 
188 	*ents = kmalloc_array(*nents, sizeof(struct virtio_gpu_mem_entry),
189 			      GFP_KERNEL);
190 	if (!(*ents)) {
191 		DRM_ERROR("failed to allocate ent list\n");
192 		return -ENOMEM;
193 	}
194 
195 	for_each_sg(shmem->pages->sgl, sg, *nents, si) {
196 		(*ents)[si].addr = cpu_to_le64(use_dma_api
197 					       ? sg_dma_address(sg)
198 					       : sg_phys(sg));
199 		(*ents)[si].length = cpu_to_le32(sg->length);
200 		(*ents)[si].padding = 0;
201 	}
202 	return 0;
203 }
204 
205 int virtio_gpu_object_create(struct virtio_gpu_device *vgdev,
206 			     struct virtio_gpu_object_params *params,
207 			     struct virtio_gpu_object **bo_ptr,
208 			     struct virtio_gpu_fence *fence)
209 {
210 	struct virtio_gpu_object_array *objs = NULL;
211 	struct drm_gem_shmem_object *shmem_obj;
212 	struct virtio_gpu_object *bo;
213 	struct virtio_gpu_mem_entry *ents;
214 	unsigned int nents;
215 	int ret;
216 
217 	*bo_ptr = NULL;
218 
219 	params->size = roundup(params->size, PAGE_SIZE);
220 	shmem_obj = drm_gem_shmem_create(vgdev->ddev, params->size);
221 	if (IS_ERR(shmem_obj))
222 		return PTR_ERR(shmem_obj);
223 	bo = gem_to_virtio_gpu_obj(&shmem_obj->base);
224 
225 	ret = virtio_gpu_resource_id_get(vgdev, &bo->hw_res_handle);
226 	if (ret < 0)
227 		goto err_free_gem;
228 
229 	bo->dumb = params->dumb;
230 
231 	if (fence) {
232 		ret = -ENOMEM;
233 		objs = virtio_gpu_array_alloc(1);
234 		if (!objs)
235 			goto err_put_id;
236 		virtio_gpu_array_add_obj(objs, &bo->base.base);
237 
238 		ret = virtio_gpu_array_lock_resv(objs);
239 		if (ret != 0)
240 			goto err_put_objs;
241 	}
242 
243 	ret = virtio_gpu_object_shmem_init(vgdev, bo, &ents, &nents);
244 	if (ret != 0) {
245 		virtio_gpu_free_object(&shmem_obj->base);
246 		return ret;
247 	}
248 
249 	if (params->blob) {
250 		virtio_gpu_cmd_resource_create_blob(vgdev, bo, params,
251 						    ents, nents);
252 	} else if (params->virgl) {
253 		virtio_gpu_cmd_resource_create_3d(vgdev, bo, params,
254 						  objs, fence);
255 		virtio_gpu_object_attach(vgdev, bo, ents, nents);
256 	} else {
257 		virtio_gpu_cmd_create_resource(vgdev, bo, params,
258 					       objs, fence);
259 		virtio_gpu_object_attach(vgdev, bo, ents, nents);
260 	}
261 
262 	*bo_ptr = bo;
263 	return 0;
264 
265 err_put_objs:
266 	virtio_gpu_array_put_free(objs);
267 err_put_id:
268 	virtio_gpu_resource_id_put(vgdev, bo->hw_res_handle);
269 err_free_gem:
270 	drm_gem_shmem_free_object(&shmem_obj->base);
271 	return ret;
272 }
273